I PRINTED an RC Car... How FAST can it go??
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- Опубліковано 29 кві 2024
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Thanks again for watching! Leave a comment if you have ideas on ways to make this thing faster. Below are links to the original and modified Tarmo5 files.
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Did you notice on the camera when you increase the speed the tires lose grip because they deform? RC fast cars use a kind of a rubber foam tire. Also you can put styrofoam inside the tires, like GoodStuff to avoid the lack of grip.
I found something that should help you build a better car: if you look at some videos of Project air, you will find out that the gyros aren't a good idea for high speed as they have a tendency to be affected by the small socks that the car experiences. The type of tyres that you need are foam one as they aren't really affected by the rotation of the wheels.
And btw, try to lower your car and reduce the amount of air that can go under it, to increase your grip, lower your center of gravity for stabilisation, and but some holes in the side parts of your chassis to try to make it lighter without losing strength
Gearing(big gear little gear)(and if you decide to go like 4 wheel drive rc like you watched on youtube the Diffs gearing) you have way too much torque the tires ballooning up like that says it all your power is on the low end right now. When i first got my electric car rc i didn't understand how to get more top end but it's all up to gearing with electric unlike nitro whereas top needle low needle and idle needle determine the tune sure you could put a bigger brushless/batteries or higher amperage speed controller but then more weight and complexity. As for tires switch to bald like tires and get them nice and hot/sticky or find a smooth asphalt road. Another option is dual high kv brushless cans(plus they tend be much smaller and lighter) so you could get the torque(tire snap) at all speed ranges but you would still have to set the gear ratio.
I recommend you get a hold of a pistol-grip style transmitter. It is far more intuitive for driving; I'm sure it will help you better understand the required control inputs when you're spinning out.
Hi! I've been driving hobby-grade RC cars for 5 years and 3d-printing for 3 so here's some tips:
1. You're right, those are definitely not the right tires for 100 MPH, they are made for a short course truck. They also experience ballooning (which is what happens when the centrifugal forces expand the tire) which caused them to fall off the rims. And yes, they should be glued to the wheels, 99% of rubber tires for RC cars have them glued. For speedruns you would use either foam tires (which have more grip and are lighter, so they don't experience balloning) or belted rubber tires.
2. The transmitter you're using is okay but it's not really meant for RC cars. It's much more comfortable to use a "pistol" type transmitter (for example a Flysky GT5, which you could use with the receiver you currently have.
3. The top speed of an RC Car isn't magic and can be easily calculated. With your setup (6s LiPo, 108mm tires, 10T pinion, 50T spur, 1000 KV (motor RPM per Volt) motor) you could theoretically reach 102.6 kph or 63.37 mph, thats assuming 100% efficiency. The formula for this car (direct drive transmission) is: [((KV*nOfCells*4,2)/60)*(pionionT/spurT)*(Pi*tireDiameter)]/1000*3,6. If you wanna convert it to MPH just multiply the result by 0,62.
4. Unless you have a perfectly smooth surface (like a strip of highway that's about to open) then you need good suspension, that is springs + damping. While the springs make the suspension "soft" or "hard" the dampers are used to make it less bouncy. You can try different hardness springs and viscosities of oil inside the shocks to tune it.
5. Despite what many people say the aerodynamics of RC cars are important. Things like spinning tires generate a lot of drag so it's best to cover them under a body. I'd look at both racing car bodies (from Protoform or Bittydesign) and speedrun bodies (Deltaplastik) and try to design something similar.
There is also a lot of stuff to consider about the suspension setup like caster and toe but with 3D printer tolerances they're less important than the things I mentioned. If you'd like to ask about something, I'd be happy to help.
Top tier comment
Excellent comment. Thank you
Awesome tips!
do you know what kind of ratio the tires are?
Some suggestions in no particular order:
- Design it to have adjustable toe. Toe-in would help a lot with stability.
- Put a good sized vertical fin from around the center to the wing, like the ones you see on 2017 Formula One cars. This would increase straight line stability by increasing the resistance to yaw and steering changes.
- Adjust the steering input to be speed-sensitive. For example: steering output = steering input / speed. Or something to that degree, whatever works best in testing.
- Your suspension - especially the rear - is probably adequate in travel and spring force, but probably inadequate in damping, if those shocks even have real dampers on the inside. Those bumps are making the rear bounce and turn, forcing the front to go that way, which causes it to flip.
- Increasing overall downforce would also help stabilize the car, and make it more resistant to direction changes from caused by bumps.
yes, toe-in is exactly what i was gonna suggest
I would add look to F1 for downforce advice...
also, you need to grease up your fancy ball-bearing driveshaft thing, and also grease up those ball joints. just adding grease would easily add 10 mph to your speed on the driveshaft. adding grease to the ball joints and any other moving parts would greatly improve performance, as especially at high speeds they will tend to "stick" if not greased up. grease reduces friction, which can help reduce wear, but also obivously helps increase movement, increasing performance.
Also, make sure the steering geometry isn’t susceptible to bump steer.
6:54 The tires ballooned. You're gonna need a stiffer set for 100mph.
Wow super cool that you were able to use my design as a launching point for your project. Great video keep it up. Some will tell you it’s not possible but I was told designing the Tarmo5 with the current specs wasn’t possible by a lot of people on the internet. I am sure you can make the design a lot better!
those cv's are super trick, no proper rc company has anything that good yet, just uj's and uj's disguised as cv's
You are great man.
You need a smoother surface.
Less suspension also some wire for some sway bars
That's the comment I was about to write. Yeah, that's the number one thing he needs,common sense !
Mars?😅
Naaa he needs to know what he wants to build has the wheels and springs of a small crawler but the wing and splitter of a formula RC
Yeah fr
A couple years ago I started down the same project 100mph 3D Printed R/C car.... I started looking at the available R/C car models and prints ultimately started designing my own. Seeing what you have accomplished I will have to start that up again.
@Daniel Toebe : Look out Bonneville... the gauntlet is down... the challenge is on! 😜
your channel has quickly become one of my favorite 3d printing channels! love the way you're always seeing what is possible with 3D printing.
I'd say you should get FPV camera + goggles and it will make your driving much more accurate immediately. Also adjust the max steering angle to be less for high speeds: either strongly non-linear control if you can avoid going to the sides during sudden movement or actually limit the steering angles similar to gaming console racing games typically do it.
An aerodynamic shell and some more weight or wider tires could give you the stability to reach 100 maybe. Gonna be a fight between friction/drag and stability I think.
Thanks for the universal vs CV joint comparison. This was helpful.
Only using 1 universal is odd.
2 is normal in this application...
Correctly phased.
@@Brettjnash this makes sense too. But CV joints are found on the cheapest of cars, wouldn't universal joints be much cheaper and stronger? But Jeep used universal joints for a really long time, but then again, they were not meant to be in 4wd on pavement, so no power going through them. I bet the difference between the two isn't that much frankly.
It was also wrong but ok
That redesign looks sick as hell. Well done on the improvements!
Some Batmobile Vibes for me
Nice video! Love to see RC content.
Foam tires will help, the ballooning hurts performance quite a bit. Also, instead of using two shocks, use one but grab stiffer springs and use thicker shock oil. A proper rc car remote is a must too, it's much easier to control. And a better road will improve stability too
-Belted tires so they do not balloon
-A body for aero dynamics, at 35mph aero drag increases to nearly rolling drag and air resistance scales with size so it is for sure a factor
Instead of installing more shocks try using stiffer springs and also use a low drag body
and stiffer oil in them, to increase the dampling
Nope, you want the softest spring possible without bouncing off the upper or lower end stops at full compression and de-compression.
He needs slower damping to reduce the high speed oscillations.
I think drag will not be a problem in a car this size
@@gtjack9 Yeah, heavier oil in the dampers would probably take care of that.
This just showed up in my recommendations and I'm glad it did! I look forward to seeing the play out.
solid rocket motor on the back ;)
I would personally recomend a "castle sidewinder" motor as they are stupid powerful even at 3s, also add another motor to the front and make it 4wd, it will be much more stable!!
Suggestion for easier steering: reduce the maximum steering values proportinally to the car's speed. That way you have way more control of the car at high speeds, as even a large rotation of the steering will only steer the car a little to the side
Awesome! I've built the tarmo 3 and 4. Now I am going to try your version of the 5!
I love that this design uses outrunner motors. They are so much torquier and hence require less transmissoin. Or even none. I've built up a 1hp/kg RC car with 4x hub motors and it turned out a blast
This is just the project I was looking for! I just started printing a 3d printed dragster for MRRF 2023 and am looking forward to seeing how fast I can go. I'll be keeping my eye on your journey to 100MPH!!
The reason your car was spinning out mainly was due to the tires. Even when you are driving on flat ground, the tire still rounds out the faster you go, making your contact patch smaller and smaller. Almost like your tires are turning into bicycle tires.
I think the number one thing you can optimize is the gear reduction, if you manage to get the amp draw the motor with the current setup at diferent speeds you can get a idea of the power/speed curve and estimate the max speed you can hit with this motor (his max power) then adjust the gear ratio to hit maximum voltage and current at this speed (migh differ a bit from theory, but it would be great start) , also try using gears with number of tooth that are prime one with another (=>1 is their only common denominator) to prevent premature deterioration
Other than a smoother surface, you may want to soften your suspension as a common reason for losing power at speed is that the bumps lift your wheels. You may also want to lower the car as to lower the centre of gravity. Adjust your front wheels to some Tow-In, probably about 1 degree. This is not so great for cornering but offers stability in straight lines. Finally, look at adding a shell of some kind. This is primarily for aerodynamics. When you hit those speeds, wind resistance becomes a real factor and especially so if your chassis has areas which are either asymmetrical or potentially look to raise the car off the ground.
I would suggest that you make a 2 motor configuration to make more power. It would also be helpful to try and make a rear wing for a bit of down-force on the rear end which will help the car to grip and go faster.
You are right about the Universal joints creating that sine wave type motion. However if you have two (the exact same way the CV joints are setup) they actually cancel each other out completely removing the oscillation. That is why any production RC car the buy uses universal joints and not cv joints.
yes and no.
on the rear, input and out put are parallel and stay that way, neglecting unequal swingarm stuff...
on the front, the wheels steer. theres the imbalanced uni joint. and the last thing you want is your front steering wheels having non-constant velocity.
unless youre a rock crawler and speeds are slow enough to not give a damn.
can always stick them on top of each other coaxially. gets complicated. CV is easier at that point.
a lot of production cars are coming with CV joints now...
Awesome video! Subscribed and looking forward to see part 2 :)
Awww yeah! Challenge accepted :)
As an enthousiast of Rc speedrunning and recent Bambu X1 carbon (& PAHT-CF) owner, you got me inspired.
Some tips:
1. Do really get a surface radio (you'll not need the gyro anymore) Control will feel way more natural.
2. Tyres are everything. There are only a few brand offering foam tyres that can do 120+ reliable. Rubbers give more grip and only a few will do so. Grap yourself some GRP GT-sized wheels.
3. Aero will reduce demand for power. But most lack of aero can be solved by power up to 100mph. You will certainly end up with a 4092 inrunner and a bigger ESC which doesn't limit your amp draw. Batteries (max amp draw and voltage sag) will be the next bottleneck. Do some research on "true C rating"
4. Stiffen up your suspention. Definately the rear.
I'm really impressed with your design, I am quite good at designing individual parts but the process you went through to design something this complex with so many individual parts baffles me. If you could create a video on how you went through this process would be amazing, or do you have any advice on how I could learn to do more complex designs like this? Thanks
Having a pistol grip transmitter will definitely make you feel more comfortable going at high speeds. I would say find a cheep Traxxas style rc and just get use to bashing it around and comfortable driving. Having a gyro compensate is fine but only after getting use to driving it plane. Also be careful of oscillations at high speeds from over compensation. I cant believe how well the printed car held up after that crash and I am so looking forward to seeing you hit +100mph. Best of luck!!
I strongly disagree about the pistol grip transmitter... conventional airplane transmitters are superior in every possible way
@@knoopx never seen any pro rc car racer use air plane transmitter. Your statement is wrong.
@@Theroux1989by the same logic, never seen a drone pro pilot, or any other hobby-grade vehicle at all, using a pistol grip. Conventional transmitters are cheaper, ambidextrous, come in different shapes and sizes, have better hardware like hall sensors with little to no deadband or drift, run on community maintained, always evolving open source firmware, can bind to multiple protocols/bands and even swap modules, including open source, low lattency, long range protocols like expresslrs, can control any kind of vehicle, support all kinds of telemetry data, inputs/outputs/mixing/trimming are 100% customizable. sticks allows for super fine, precise and agile control and are not monopolized by one or two companies that haven't evolved since the 80s. not even a $700 futaba is objectively better than a $200 radiomaster. and yes... I have extensively used pistol grips in the past and hated them so much that went to the extend of reverse-engineering their propietary protocols so I can use my own, single transmitter to control all my rc vehicles...
@@knoopx As a guy that has Raced RC's at national champion level(I got third out of seventeen)
And also flies RC drones and Heli's
Pistol grips are way better on RC cars than stick's because of the way the controls work(have driven RC cars with sticks and it's a pain in the butt)
Drone pilots cant use pistol grips(duh GL flying a drone with only two fully proportional channels)
You dont like them But there is a reason why all pro RC drivers use pistol grips(including my buddy which has been the national Electric and Nitro buggy champion here for the last four years)
@@storm4710 sure, braking control is superior indeed, and although preference is not a technical aspect of it, it also plays a very strong role. thing is people is recommending a pistol grip like it is going to magically solve the car stability issues when it will make no difference and he's better keeping that radiolink and focusing on the root issues.
thank you. I thought only thingiverse existed till now. I've checked Printables, and it's awesome!
This is awesome! I also went down the rabbit hole of 3d printing RC cars and ended up redesigning a traxxas rustler 2wd, reusing the gearbox and drivetrain to create my own 3d printed speed demon. It’s got some reliability issues especially since i run it on 8S, and it’s gotten up to 60mph so far but I’m aiming for 100+. Gearbox is the main issue ironically. This video has got me thinking about doing a more custom build with printed drivetrain parts and such.
A couple things you should do: buy a set of Hoons or GRP tires, lock the front suspension with a nice, ductile nylon or TPU filament, and lower your center of gravity. Make the wings a higher angle of attack, at this size a flat plate performs relatively efficiently compared to an airfoil. Get a much bigger inrunner motor, and make sure it’s rated for your ESC’s power output while providing adequate torque. These are all things I did and my car runs awesome on a good surface. Great work!
I have wanted to print my own car for a long time. This definetly is a cool project.
you might want to be careful when going at higher speeds with a gyroscope because you can get unwanted oscillations AKA fishtailing and completely loose control of it. also to avoid excessive tire ballooning you can wrap some fishing line between the threads on the tires or go for some foam ones. good luck and Godspeed!!!
You just got another subscriber. Really cool project, I've seen many or most 3d printed cars, but this somehow feels better and more awesome. Great video! ❤
Very nice work. I was dreaming to have this kind of project decades ago. Now there are 3Ds and since that, I believe things can make it highly possible. I would suggest to put in dynamic shock absorber, differential drive and brake system by making individual motors for each wheel etc. to overcome flip and increase stability.
very nice and can not wait to see where you go from part 1. I would try to enclose or at least reduce the drag that the compartments cause. It might not be much but every little bit can help.
Great job man, that thing ended up driving better than a brand new one I just bought lol. There are a ton of little details and caveats to good steering and control but somehow a 3D printed deal like this handles it all really well for what it is. I recommend some good oil filled shocks!
I want more of this RC car man! Good Stuff!
Amazing video! Can't wait to see more.
I only recently got a 3d printer, it has a tiny build volume (100x100x100mm), but this makes me excited to try and make something like this. I've made various rc cars using Lego technic, so I think I have enough knowledge to now do it fully custom, heh
Honestly you just need some foam tires, sway bars and less suspension travel. Also needs way more power. But you should not focus big on aero, you just need a wing at the back to keep it straight, but at 100mph you mostly just need power
tire blow off was priceless. As a guy who had MANY RC cars using glue on tires is a must for traction and staying on rim lol. This thing is pretty damn cool too! Cool video bud
Can you post the STLs and BOM list? I like your design and will definitely make one. I would suggest getting the batteries as low as possible to lower the center of gravity. Also look in to either metal gears, or print them form better materials, at least abs or higher temps. Also lube them up! Great build
The carbon fibre nylon would probably be suitable for gears, they usually don’t recommend you use it with other materials due to the abrasiveness but it should be fine with itself, plain nylon is also very good for gears since it is self lubricating. PLA is likely to melt but if you have enough friction to melt other materials then something is wrong.
@@conorstewart2214 wouldnt cf-nylon gears cause more friction due to the chopped carbon fiber inside the filament that results in a rough exterior? it is also very hygroscopic so many lubricants will be absorbed into a gear made of cf-nylon.
@@doctordookiemf the carbon fibre would improve wear resistance but may add a little friction. Nylon is very often used for gears, it being hygroscopic isn't an issue. There is also a difference between water and oils getting absorbed. Something like lithium grease works well and doesn't cause any issues. Also nylon is self lubricating so you may not need any lubricant.
@@conorstewart2214 PLA is great for gears except for the very first motor pinion gear. Even then I've used PLA gears on low current motors who's shaft doesn't get warm. There is no reason to use fancy materials...
And for that matter, I'm not sure any 3d printed motor pinion gear for attaching to that outrunner bell is going to not suck. Broke on the layer lines in the video, good luck printing in any other orientation that also won't just split in half.
Universal joint can give you a constant speed but you need two of them. Your suspension is build in the way that the inner shaft is ALWAYS parallel to the wheel shaft. So if you put two universal joints, the will cancel each out. On the test stand you have only one "bend", so the rotation has oscilations, but if the shafts of the gearbox and the wheel are paralell then two oscilations in the universal joints has opposite phase.
This chassis is amazing and your mods are awesome ! pretty good work
I'd install roll-bars front and rear, lower the suspension and make it as tight as possible as well as replacing those 3D printed links for the steering with nice adjustable ones ;)
Ah, I almost forgot ! Race tires ! Damn !
Lol this is quite insane, hitting these speeds on a printed car. Well done!
AWD is going to be essential for stability at high speeds. Also, make sure you have high quality shocks with adequate weight RC shock oil in there.
Super cool project, glad I found your channel!
what a great piece of engineering!
Nice work! Insane how refined that design is and has become over the years. One thing that you probably already know: your tires are badly deforming at high speeds, and I think that's really hurting your stability. Might need to 3d print larger rims and then make solid or nearly solid tires out of TPU or something.
clicked immediately. going to try to recreate this over the summer.
awesome work! consider aerodynamic stabilization; a bit of aero drag behind the cg will help. you need to keep it low to the ground so you don't induce a pitch up moment. downforce helps too. there's lots of well understood profiles, but I think it would be cool if you make a diffuser work well
This is going to be great!
Great project, thanks for sharing
** Edited *** Found parts list, Great video! Subscribed!
As your tyres rotate faster the contract patch goes from square to a tiny oval. Meaning you get far less contact area at high speeds.
You could buy high speed tyres, 3D print some, glue foam into them to stop the middle expanding, or 3D print inserts you for into the true and run to stop them being able to deform at high speeds.
as RC modelar this was amusing to watch:D The rookie problems united in one go:D haha, you did well!:)
I think reducing the suspension travel and moving to stiffer springs would help with stability. Also it would be good to look into foam tires, which are what a lot of the rc speed cars use.
It just needs slower damping, stiffer springs will just increase the frequency of the oscilllations and make it more likely to jump around.
Longer travel, the lowest spring rate possible without hitting the bump stops, and a much slower damping setup, the current setup doesn’t appear to have any damping.
i don't understand your point about longer travel, why longer travel would be better ? if you have some demonstration of that it would be very intersting for me as i'm currently studying oscillators. @@gtjack9
it would also be a good idea to look into belted tires. they don't blow up or expand. great video!
Fastest 3 D printed RC … love it 👍👍👍good luck
This is fun. I kind of want to see TPU printed tires. This makes me want to build my own
Audio guy here,
Nitpick, at 1:57 you mention the velocity fluctuating with a sine wave.
A Sine wave is a lot less jagged, very smooth and round. You showed something that looked like a slightly distorted triangle wave.
Love the video tho, first one I see from you and I will check some of your others :D
Im making an rc car in my shop class with a brushed motor and low power traxxis components. It probably makes a bit less than 1 horsepower and doesnt have suspension, but i got it up to 40 mph on my schools track. It was previously capping out at 30 mph, but the addition of a simple cardboard aerodynamic body made it jump 10 more mph. In conclusion, you could add a body to make it way faster.
As someone who has a couple of old rc cars for which parts are nonexistent, you convinced me to try and look into 3d printers!
To fix the "de-beading" issue with the tires. You can use a popular drag racing and offroading design called a "bead locking wheels". Instead of glue, it's a clamp.
When the tyre balloons the contact patch / grip will significantly reduce. I would look at getting ones with internal re-enforcement if you want to go faster :)
This is what pure joy looks like 👍
print the motor gear at an angle(about 45*) to reduce the stress on one layer. it helps a lot.
A little bit of toe in should make it more stable on straight line but also it increases the rolling resistance, also fix the ballooning of your tires and put a shell on it.
Inspiring stuff! Can't wait to see the last leg of your journey when you blow past the goal :D
I think starting out with an elevated driving position would up your stability significantly. Add braking, and lower your rates, you don't need much steering travel at speed.
that was the best thing I've seen on the internet! thanks
The motor that spun to say subscribe earned yourself a subscriber 👌🏻 clean 😮
You should try placing the electric motor in the middle of the car right infront of the cv axles, make a rear diff for it. You might be surprised at the results like I was when I designed a similar kind of setup for a go kart sized vehicle.
Great job! 🎉
Great work, and amazing content.
its a cool experiment hands on
'Preciate the MJF entrance bgm
I've been upgrading rc cars recently and had built one that went way too fast and had the same issue. Super glue definitely works haha
Sick! great work!!!
The specifics of this are really interesting
This car looks very good for a 3D-printed, nice design! Can you share your improved design too?
He did if you would have looked in the description of the video :)
@@ZillionPrey Oh, you are so kind! Thank you for your reply :)
Nice video shot, keep it up, thanks for sharing it :)
Thank you for this.
Ill be buying a Bamboo soon and an RC car is going to be my first project.
You should change the tires to tirea which can actually handle higher speeds, as they wont balloon (come off the rim) as easily. This will also improve stability at high speeds
You can use TPU on some of the suspension parts to have natural shock absorption, that'll also make them less likely to break in a crash
I like that the on car camera makes it look like a 3rd person perspective of a Tamagotchi pilot.
What I noticed when you get to the higher speeds, the tyres elongate which is probably why it's becoming unstable at higher speeds. I would consider looking into a harder compound of tyre to try and mitigate that. I'm guess that the tires don't actually have any pressure in them, but I bet if you had a rim and tyre that can take pressure you would eliminate this problem.
Now looking at the next video you totally did that lol. Anyways good stuff!
nice work - I still think having a solid metal baseplate helps. It gives stability and lowers the center of gravity. And I'm not quite sure about printed gears - but if those break, then nothing too bad will happen?
An RC car remote will have to ability to setup trim and sub-trim. When you drive your car it slowly moved to the left and you have to correct it at high speeds, with sub-trim, you can make small adjustments to where the car will go dead straight when you aren't steering either way on the stick. This is a standard setting for any RC car racer for their setups. It will save you a lot of heartache.
Here are a few things you can do to improve the stability:
-Adding some toe-in to the front wheels will help it track straighter. (Toe-out will improve handling in the turn but won't track well) Loose linkages will add toe out, which will cause wandering. For that reason, you should use adjustable tie-rods so you can make adjustments.
-Add 1 or 2 degrees of of toe in on the rear wheels too. This really helps when accelerating, which seemed to be a problem in the video.
-Lower the suspension. Your ride height should be only as high as it needs to be, and since you're running on flats, keep it low.
-Get some better shocks. Losi 22 or 8ight shocks will be MUCH better and still let you have loads of suspension if you want to go offroad. The shocks you have look like they're meant for low speed toys or rock crawlers or something.
-Your springs and shocks should be set up so that there is approximately as much down travel ad there is up travel. That is to say, when you set your car down, the suspension should compress at least half-way. If you're riding at the top of your suspension travel all the time, the wheels are constantly leaving the ground. Having down travel helps keep the wheels on the ground, which keeps you in control.
-Your rear shocks are too angled in at the top. They should be about half way from where they are to vertical. This is part of why you needed to add a second set of shocks - the more angled the shocks are, the less weight they can carry.
-Your front shocks are angled the wrong way. They should be angled more like the rears, but not as much. This matters a lot. Angled in make the suspension progressively more stiff as it compresses, which helps control body roll. Angled out makes it progressively less stiff as it compresses, which makes body roll worse... that's bad.... really bad.
-Move the motor to in front of the the rear axel rather than behind it, and the battery mounted transversely in front of that. This will give you better weight distribution.
-Change your wheels to 1/8 scale buggy wheels. You're using short coarse truck wheels, which are designed for off-road. This will require a different hub, so get the wheels first and design to match.
-Gluing tires to rims is a must... always. clean the surfaces well, and use lower viscosity, high quality CA to penetrate the gaps better and get a stronger glue... don't use the supermarket stuff, it's not as strong. You'll need a good bond if you're going to go 100mph...
-Use some decent tire inserts. This will help keep the tires from deforming as much.
-Get a ground transmitter. The old stick controllers just aren't as good for cars... (It is a matter of preference, but you don't see a lot of stick style transmitters these days for RC cars... by which I mean for the last 30 years or so. As someone who has been doing this long enough to have used both, and even made the transition from sticks to pistol, AND as someone also into RC planes, I would have to concede that pistol is better.)
-I'm not sure what you have for a steering servo, but consider getting a quality steering servo if you don't have one. This will make a night and day difference. You want something with good speed and torque... It doesn't matter how well you drive, or how good your gyro is, if your steering servo can't react fast enough.
Cool video. I use that same Lipo charger for FPV quad batteries. Thanks for the future project
I loved it good job man
- You definitely need to switch to foam tires.
- Is there any oil in the shocks? The car looks bouncy as hell. If there is, switch to a heavier weight.
- Convert it to 4wd, there aren't a lot of 2wd speed run cars around.
- angle your wing and splitter so they produce some actual downforce, but not too much. Might as well throw a body shell on, too.
As a past RC Oval National Champion, speed is all about the less friction you have the better. Your main gear I called it a Spur gear and your motor gear a pinion gear is too big and bulky. Try and modern brushless motor setup with a modern spur gear and pinion, you will be amazed at the results. Also for steering the less steering you have for just going straight would be better, a very slight toe out would make it more stable. The rear arms with 0 degree toe out would be for all out speed, or a very slight toe in for a bit more stability. Also get a modern radio setup with the trigger and steering wheel control, much easier. Now this is all pending on what kind of budget you have. :) I wish you much success.
Great project! Thanks for sharing! Could not having a body cover be causing strange areas of drag, thereby causing instability? Lol seems like there’s lots of great suggestions.
It’s crazy your doing this. I’ve been also printing a few different designs with a speed goal. The biggest problem you will have is stability. I’m on my 4th variation and so far can’t hold straight above 45-50mph.
Try drag tires on the rear and smaller up front. Hurts the turning but it goes straight. If speed js the goal you need to get the nose down so wind can flow over.
Instead of making 3 compartments inside the car, make one, so the floor is stable/rigid, but the weight is reduced - take a peek on arrma/traxxas/hobao chassis. Distribute mass evenly. Use body shell (especially low drag body shells), just this one will give you a boost in performance. Also - strip additional shocks - if the shocks you have are not stiff enough - change the oil that it is filled with. If the length of the shock is the problem - put a small piece of ptfe tube on it, to limit the travel.
Loved the video! Also got a few tips for you:
Put a RC Body on it. That would help an insane amount, when it comes to aerodynamics.
Buy different tires! These things are offroad tires and not even belted, meaning they expand at high RPM, which isn’t good for stability.
Use a proper RC Car remote, not an RC plane one. That would make it way easier to control.
Hope this advice helps.